Was John Demjanjuk a victim of mistaken identity?

The hunt for a monster can warp the pursuers. The wanted man was one of the most loathsome creatures of modern times: "Ivan the Terrible," who hacked at his naked victims with a sword as he herded them by the thousands into the gas chambers he operated at the Nazi death camp Treblinka. American and Israeli officials were certain they had found him in John, formerly Ivan, Demjanjuk, a retired suburban Cleveland autoworker of Ukrainian descent. He was extradited to Israel in 1986, where he was convicted of crimes against humanity and condemned to hang after a dramatic trial that transfixed...